<!DOCTYPE html>
<html lang="zh">
<head>
    <meta charset="UTF-8">
    <title>03-常见属性-边框</title>
    <style>
        div {
            display: inline-block;
            background-color: #f00;
            border: 5px solid #0f0;

            padding: 20px;
            margin: 50px;
        }
    </style>
</head>
<body>

<div>我是div</div>
<br>666

</body>
</html>